#!/usr/bin/perl use strict; # https://perlmonks.org/?node_id=11115029 use warnings; my $newline = promptandreviseline( "Previous Value : ", 'previous line' ); print "The New Line is: $newline\n"; ###################################################################### use Term::ReadKey; use Data::Dump qw( pp ); sub promptandreviseline { my ($prompt, $line) = @_; $line //= ''; $line =~ tr/\t\n/ /; local $| = 1; my $startcolumn = 1 + length $prompt; print "\e[1G$prompt"; my $cursor = length $line; my $pos = $startcolumn + $cursor; print "\e[${startcolumn}G\e[K$line\e[${pos}G"; my $more = 1; ReadMode 'raw'; while( $more ) { sysread STDIN, my $input, 4096 or last; for my $key ( $input =~ /\e[^\e]+|./gs ) { if( $key =~ /^[\cc\e]\z/ ) { $more = 0 } # ^c escape elsif( $key =~ /^[\n\r]\z/ ) { print "\n"; $line .= "\n"; $more = 0 } elsif( $key =~ /^[ -~]$/ ) { substr $line, $cursor++, 0, $key } # char elsif( $key eq "\b" ) # backspace { $cursor > 0 and substr $line, --$cursor, 1, ''; } elsif( $key eq "\e[3~" ) # Delete { $cursor < length($line) and substr $line, $cursor, 1, ''; } elsif( $key eq "\e[D" ) { $cursor > 0 and $cursor-- } # left arrow elsif( $key eq "\e[C" ) { $cursor < length($line) and ++$cursor } # right elsif( $key eq "\e[F" ) { $cursor = length($line) } # End elsif( $key eq "\e[H" ) { $cursor = 0 } # Home else # invalid, show sequence { my $seq = pp $key; substr $line, $cursor, 0, $seq; $cursor += length $seq; } $pos = $startcolumn + $cursor; $more and print "\e[${startcolumn}G$line\e[K\e[${pos}G"; } } ReadMode 'restore'; return $line; }